Leah Francesca Rosin, Ph.D.

The Unit on Chromosome Dynamics combines genomics approaches with advanced microscopy in multiple model systems to investigate the regulation of germ cell development. Precisely regulating the genome in all cell types is absolutely essential for cell function. In the germline, genome regulation is a highly complex process where some cells (germline stem cells and somatic germline cells) are mitotically dividing, but other cells exit the mitotic pathway and undergo a complete reprogramming to contribute to the next generation as egg or sperm cells (meiotic germline cells). Understanding the chromatin dynamics and epigenetic changes involved in determining and maintaining these different cell lineages is critical for understanding germline maintenance and fertility.

One of the most poorly understood aspects of meiotic germline cells is homolog pairing. During meiosis, maternal and paternal copies of the same chromosome come together and pair from end to end. Errors in pairing lead to increased chromosome missegregation or meiotic arrest, which decreases fertility, increases the rate of miscarriages, and increases the likelihood of chromosomal disorders in progeny (such as Down Syndrome or Turner Syndrome). Yet, how homologs find each other and form stable linkages with each other remains unclear. This gap in our understanding of chromosome biology is partially due to the fact that it is extremely challenging to study pairing in mammalian systems, where pairing is restricted to a subset of specialized cells in the germline (and in female mammals, all meiotic pairing happens during embryogenesis). Thus, employing multiple model systems and elucidating what aspects of chromosome pairing regulation are conserved across species is essential for making accurate inferences about human biology. One of the main goals of my lab is to employ a combination of insect and mammalian systems to dissect the mechanisms regulating homolog pairing and inter-chromosomal communications across species. Understanding these central aspects of chromosome biology will not only provide insights into how disruption of these processes can result in genome instability but will provide new avenues for potential therapeutic targets for infertility.

- Earl Stadtman Tenure-track Investigator, Unit on Chromosome Dynamics, Division of Developmental Biology, NICHD, 2023 - present

- NIH K99/R00 Pathway to Independence Award, 2021

- Postdoctoral training, Laboratory of Dr. Elissa Lei, Nuclear Organization and Gene Expression section, NIDDH, 2018 - 2023

- Postdoctoral training, Laboratory of Dr. Eric Joyce, Penn Medicine, 2016 - 2018

- Ph.D. in Genetics and Genomics, Laboratory of Dr. Barbara Mellone, University of Connecticut, 2010 - 2016